A retrospective review of the management and outcomes of patients diagnosed with complex regional pain syndrome type II using electrodiagnostic findings.

Objectives: The objective of this study was to assess the outcomes of the use of electrodiagnosis in the diagnosis and management of discrete nerve injuries in patients with complex regional pain syndrome (CRPS). Design: This study is a secondary retrospective cohort analysis of patients diagnosed with CRPS from a single outpatient physical medicine and rehabilitation clinic and included all patients who had abnormal electrodiagnostic findings, in addition to CRPS. Results: Sixty patients of 248 diagnosed with CRPS underwent electrodiagnosis, 41 of whom had abnormal electrodiagnostic findings indicating a discrete nerve injury. Only 51% of the 41 referrals had indicated the suspicion of a nerve injury. Nearly all patients had undergone physiotherapy. Forty-one percent responded to treatment with oral prednisone alone, 54% had a functional improvement after a combination of treatments including corticosteroids, and 5% improved with treatments that did not involve corticosteroids. Surgical interventions for nerve injuries were required for 34% of patients in the cohort. All surgeries involved the median or ulnar nerve, with the exception of one fibular nerve. After treatment, 39 of 41 patients had functional recoveries or better. Conclusions: Electrodiagnosis can inform diagnosis of nerve injury and direct intervention including the need for surgical intervention. Electrodiagnosis should be considered for patients with initial signs of concomitant discrete nerve injury or with CRPS who are not responding to treatments because a nerve injury may be underlying.